Earnings Per Share (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Earnings Per Share [Line Items]
Stock Repurchased During Period, Shares	118,613
Treasury Stock Acquired, Average Cost Per Share	$ 26.49
Share Repurchase Program [Member]
Earnings Per Share [Line Items]
Stock Repurchased During Period, Shares	72,706
Stock Repurchase Program, Authorized Amount	$ 25.0
Stock Repurchase Program Expiration Date	Aug. 31, 2015
Amount paid to repurchase shares	1.8
Shares Repurchased Under Stock Compensation Program [Member]
Earnings Per Share [Line Items]
Stock Repurchased During Period, Shares	45,907
Amount paid to repurchase shares	$ 1.3

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

+ Details

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Definition

Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

+ Details

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